Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8338f4f12aa22cbc3b46651f78872e3cf7cb0f90d13f12d4c393ec4c2c931ff4' 
  AND token = 'c66tyNCWDmflF19UDM9jVaDlta6iDuj0fsQJpECxxHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}